A bridal shower is a gift-giving party held for a bride-to-be in anticipation of her wedding. The custom today is most common in the United States, Canada, and by American influence, in Australia. Showers are usually coordinated by the bridesmaids, who invite guests to offer gifts for the upcoming home of the bride and groom as a married couple (or more accurately of the bride, since the groom is very seldom invited to the shower).

The history of the custom is rooted not necessarily for the provision of goods for the upcoming matrimonial home, but to provided goods and financial assistance to ensure the wedding may take place.

Many different customs have developed in different regions and social groups. But the basic format has been relatively unchanged for generations, and emphasizes traditional gender roles. Sociologists like Beth Montemurro note that the ritual of the bridal shower "socializes women into the hyper-feminized traditional wife role," with its emphasis on the future role of the bride-to-be as family cook, homemaker, and sexual partner. But this role is more of an homage to the mothers and grandmothers than a reflection of how the bride-to-be will actually behave in the marriage.

Traditionally, hosting the bridal shower falls on the maid of honor. Because gifts are required of those who attend the shower, some communities consider it rude for a relative of the bride to host it, but relative-hosted showers are a common and accepted occurrence in other communities. The shower normally takes place four to six weeks before the wedding.

Due to the prior history of showers being "purely spontaneous and informal", showers have not developed the same formal etiquette that has developed with respect to weddings. It is not customary for guests to receive formal invitations in the same manner as they would for a wedding.

Source: wikipedia.org